The invention relates to a positioning arrangement for use with a device with a fixed or movable crane arm, wherein a tensile stressed means hangs from the free end of the crane arm for the vertical hoisting and lowering of a suction device for holding plate-shaped bodies in a defined position, the suction device being suspended at a point of attachment and a tilting device being attached to the suction device.
Such devices are, for example, used at the processing and treatment of glass panes, and especially during the installation of glass panes at construction sites. In this connection, the suction device is used for holding the glass pane, which can then be transported by means of a lifting apparatus, for example, a crane to the desired place.
As a rule, the suction device provides several suction heads, which are arranged side by side in a row on a traverse. The device for vertical hoisting and lowering of the suction device is attached to the traverse. Since the installation of the glass panes is performed in most cases in the vertical position, the suction device is centrally applied in the upper half at the glass pane. With this kind of holding, the glass pane never reaches a vertical or nearly vertical position because of the unfavourable position of the center of gravity. Difficulties occur, especially during the installation of very large glass panes, when the glass pane which is not vertically arranged while being transported by the crane is to be brought into a vertical mounting position.
A device of the above-identified type is already known (DE-GBM No. 1 973 589) wherein the tilting device attached to the suction device provides curved paths, on which pulleys slide which are provided at the end of the tensile stressed device. The suction device with the attached plate-shaped body can be pivoted between two end positions due to the shape of the curved paths, the plate-shaped body either being in an almost vertical position or in a horizontal position. A completely vertical position cannot be achieved, since, in both end positions, the center of gravity of the formation consisting of the suction device and the plate-shaped body is not below the tensile stressed device.
On the other hand, the suction device with the attached plate-shaped body is mounted in a stable manner only in the two end positions. In all interim positions, the suction device with the attached plate-shaped body does not remain stable.
Moreover, a device is known (DE-PS No. 413 160) which enables a plate-shaped body to be brought from a tilted position to an almost vertical position; however, a vertical position of the plate-shaped body can never be achieved by means of this device, since the point of attachment of the cable rope holding the suction device lies vertically above the center of gravity of the suction device itself but not above the formation consisting of the suction device and the plate-shaped body attached thereto.
Because of the existence of another known device, the variation of the position of a glass pane hanging on a suction device by varying the point of attachment at the suction device is already state of the art. In the paper "VerglasungsGehange (8/82)" of the company Pannkoke, Flachglastechnik GmbH, Hendelweg 5, 2400 Lubeck 1, Western Germany, a suction device is described which serves for the hoisting and lowering of glass panes within an angle of 90 degrees. There, the point of attachment at the suction device can be pneumatically moved in the lifting apparatus parallel to the suction plane. However, with this known device, the glass pane may not be brought in a vertical position.
An important object of the invention is to provide a device of the above-mentioned type, by means of which a plate-shaped body may be held in a vertical position even if the free end of the crane arm is below the upper edge of the plate-shaped body.